Samsung puts only 1gb ram and fills it with all kinds of it's own services that use all the ram and bug down the system:
Solution:
-Replace Touchwiz with Go Launcher HD.
-Root device and freeze all Samsung stuff that boot up with the system which you don't need such Samsung hubs(games, news etc), Yahoo services etc. Titanium backup can be of help to freeze.
-uncheck cpu in power savings option.
-reduce or stop animations in developer options.

maybe u got defect tab 3 ,try antutu benchmark and see how much u get score?
I had tab 3 7.0 got so slow with only 8800 score, and its got RMA due to auto shut down motherboard,and they give me new tab3, now its score 12000-13000pts,more faster and smooth.

I was going to start the same thread before I saw yours. The SGT3 is a horrible tablet, cheaply built, slow, antiquated resolution and overpriced. I bought one after my Asus Infinity 700T was stolen after a visit too a library. When I went into the store to buy a new tablet I asked the sales person what he would recommend, I had a budget of 300. He excitedly showed me the Samsung Galaxy Tab 3 10.1, the demo unit unfortunately wan't able to start, an omen I should have realized. I was impressed by the size and weight, the cheap plastic feel was worrying but the latter two plus's were enough for me to pull the trigger. When I got it home, charged it, setup up all of the user credentials, the first thing I noticed was how cartoonishly big everything looked. I did however like the look of the keyboard, so I pushed on and installed all of my favorite apps, I started to notice a lot of lag when installing apps, okay maybe the Play Store just isn't optimized for the x86 CPU, I continued. When the tablet was finished installing, I rebooted, than the nightmare what is Tab 3 started. First I tried surfing with Chrome but when more than 6 tabs are opened, do to the lack of memory you will loose whatever you have typed in one tab after you switch to another. The system is very sluggish, typing with a Logitech Keyboard in QuickOffice, the screen can't keep up with my typing. I can spend all day going through all of my apps and describing to you how slow each one performed but you get the idea, SLOW. I wanted to comment on the screen, the resolution is ridiculously bad for a 300 dollar 2014 tablet, I am actually shocked as to how bad it is. It's bright enough but man, Samsung has gotten so cocky to think that they can shove this crap down our throats. Not to mention how easy it is to scratch, breath on it and it's scratched. I decided to try installing a custom ROM for giggles, I had already decided to return it, wow slim pickings in that arena. The two I found were also really bad, the tablet was a little faster, memory management improved a little, not sure why the developers thought that changing the look of the color scheme for the notifications tab was a good idea, the ROMs did nothing to improve the overall experience though, nothing.

I returned the Tab 3 after only two days of what I would call the worst experience I have ever had with a gadget and bought a Nexus 10. 100x the better machine, it even cost 30 dollars less and has built in HDML. Oh the HDMI, I forgot about the HDMI, Samsung charges 40 dollars for the HDMI cable, it however doesn't charge the Tab 3 when connected and because the battery is so bad you can maybe watch a movie and a half. It also doesn't output 1080P when your in the desktop, just 720P so everything is fuzzy. Stay away from this tablet people, it's bad, expensive and insulting to the consumer.

Stay away from this tablet people, it's bad, expensive and insulting to the consumer.

I'd have to heartily disagree with you on that. I've had mine for a few days now and it's everything I expected and then some. Even before I froze a ton of stuff it was lagfree for me. Yeah the resolution kinda blows but it's a tablet. If you want 1080p look at your monitor, 720 is more than fine for a mid-level tablet. As for the Nexus, well I'd have to say the Tab is better but my opinion is jaded because it has a SD Slot, that's a monumental dealbreaker for me when it comes to the Nexus. You talk about it being 2014 well in that case the Nexus should have an SD Slot, that's an archaic thing do by not including one. Not everyone wants to cloud everything.

Regardless, this tablet is more than competent. There is a reason it has a huge community and such great ratings everywhere, it's probably one of the highest quality tablets for its price.

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